Histopathology - Upper GI disease Flashcards
What is the “Z line” in the GI tract?
Normal appearance of squamo-columnar junction (epithelium transitions from squamous to columnar)
Z line in the oesophagus is the term for a faint zig-zag impression at the gastro-oesophageal junction that demarcates the transition between the stratified squamous epithelium in the oesophagus and the intestinal epithelium of the gastric cardia (the squamocolumnar junction)
Where is the cardia portion of the stomach?
Junction between oesophagus and stomach
What are the 3 layers of the stomach wall?
Gastric mucosa (columnar) Lamina propria (containing glands) Muscularis mucosa
In a normal duodenum, what is the villous:crypt ratio?
3:1
Where are goblet cells usually found?
Intestine
(NOT in stomach)
What is the most common cause of acute oesophagitis?
GORD
If reflux oesophagitis causes a perforation of the oesophagus, what will be the result?
Mediastinitis
What are the 4 most common complications to remember of most GI pathologies?
Ulceration
Haemorrhage
Perforation
Stricture
What is gastric metaplasia?
type of CLO without goblet cels
Metaplastic change in oesophagus WITHOUT goblet cells
What is intestinal type metaplasia?
type of CLO with goblet cells
Replacement of squamous epithelium with metaplastic columnar epithelium WITH goblet cells present
higher cancer risk in this type
What is the most common sequence of pathological progression to cancer in the upper GIT?
Metaplasia –> dysplasia –> Cancer
What is the most common type of oesophageal cancel?
Adenocarcinoma
Where does adenocarcinoma of the oesophagus usually develop?
bottom 1/3 of oesophagus
Which type of oesophageal cancer is most strongly associated with GORD & Barrett’s?
Adenocarcinoma
What is the most common type of oesophageal cancer in developing coutries?
Squamous cell carcinoma
Which type of oesophageal cancer is most associated with smoking and alcohol?
Squamous cell carcinoma
Where in the oesophagus does squamous cell carcinoma tend to present?
upper 2/3 of oesophagus
Why is prognosis for oesophageal carcinoma particularly poor?
Most patients are not suitable for resection surgery
What other condition are oesophageal varices particularly associated with?
Portal vein stenosis/hypertenion
What are the 3 main causes of acute gastritis?
Aspirin/NSAIDs
Alcohol
H pylori
What are the 4 major causes of chronic gastritis? Where do they affect in stomach
ABCDs of chronic gastritis
Autoimmune (antiparietal cell antibodies affects body)
Bacterial (H pylori, affects antrum)
Chemical (NSAIDs, bile reflux, affects antrum)
D = IBD
Which types of neoplasm is H pylori associated with?
Adenocarcinoma
Lymphoma (MALToma)
How do some H pylori inject toxin into the mucosa?
Via cag A needle appendage (Cad A +ve h pylori have this)
(as they can’t directly invade epithelium)
Which strain of H pylori is associated with more aggressive chronic gastritis?
cag-A positive
Why might you biopsy a gastric ulcer?
ALL gastric ulcers should be biopsied to exclude malignancy
What will be the result of a perforated gastric ulcer?
Peritonitis
What is gastric epithelial dysplasia?
Abnormal epithelial pattern of growth but no BMembrane invasion
What is the key cytological feature of gastric epithelial dysplasia?
High nuclear cytoplasmic ratio
What is the difference between gastric dysplasia and gastric cancer?
Invasion of basement membrane
What type of carcinoma is the most common type of gastric cancer?
Adenocarcinoma - 95%
Where is gastric cancer most common?
Japan, by far
What are the morphological categories of gastric cancer(specifically adenocarcinoma)?
Intestinal
Diffuse aka signet ring = poor prognosis
What is the pattern of intestinal gastric adenocarcinoma?
Well-differentiated (mucin containing glands)
What is the pattern of diffuse gastric adenocarcinoma?
Poorly differentiated
Signet ring cells, Linitis plastica
What is linitis plastica?
No focal lesion in stomach, but whole thing is thickened and static - due to diffuse adenocarcinoma
What is a gastrointestinal stromal tumour? (GIST)
Tumour of the interstitial cells of Cajal in the stomach - a SARCOMA
What is the cause of gastric MALToma?
Chronic inflammation, usually due to H pylori
What are gastric MALTomas composed of?
B cells
What is the first-line treatment of gastric MALToma?
H pylori treatment, could reverse lymphoma
Which type of gastrointestinal tract ulcers are always benign?
Duodenal
What is cryptosporidiosis?
Protozoal GIT infection causing diarrhoea seen in immunosuppressed patients
Where does giardia lamblia infection cause pathology?
Villi of GIT
What is the route of transmission of giardia?
Faeco/oral route
what cell damages villi in coeliac disease?
Cytotoxic T cells
In what condition are increased numbers of intraepithelial lymphocytes in the GIT seen?
Coeliac
What are the 3 main histological features of coeliac?
Crypt hyperplasia
Villous atrophy
Increased numbers of intraepithelial lymphocytes
Which two antibodies are required for diagnosis of coeliac disease?
Endomysial Tissue transglutaminase (TTG)
Where is MALToma associated with coeliac likely to be located?
Duodenum
What is the type of MALToma as a result of coeliac disease called?
Enteropathy associated T cell lymphoma
distinguish between ulcer and erosion
ulcer past muscularis mucosa (into submucosa)
erosion before muscualris mucosa (not into submucosa)
define barrett’s oesophagus
metaplastic process where squamous epithelium of lower oesophagus are replaced by columnar epithelium
aka columnar lined epithelium
metaplasia vs dysplasia
Metaplasia: Transforms a cell from one form to another; caused by external stimulus; can be reversible; less likely to lead to cancer. Dysplasia: Transforms a cell into an abnormal version of itself; caused by internal stimulus; is not reversible; more likely to lead to cancer.
compare the histology of SCC of oesophagus and adenocarcinoma
SCC - invades submucosa, cells form keratin
adenocarcinoma - glandular epithelium, mucin
which cells are involved in acute vs chronic gastritis
acute = neutrophils chronic = lymphocytes
define malt. what do you see on stomach biopsy
lymphoma associated lymphoid tissue
= chronic gastritis associated w h pylori
biopsy - lymphoid follicles = highly suggestive of H pylori as not normal
what cancers do atrophic vs non-atrophic gastritis progress to
atrophic = adenocarcinoma non-atrophic = MALToma
antrum predominant gastritis progresses to?
duodenal ulcer
outline the 2 pathways that lead to GI cancers
metaplasia-dysplasia pathway = upper GI e.g oesophageal cancer
adenoma-carcinoma pathway = lower GI e.g colon cancer
give an example of a neuroendocrine tumour of the stomach. what condition is this seen in sometimes
Zollinger Ellison syndrome
a condition in which a gastrin-secreting tumour or hyperplasia of the islet cells in the pancreas causes overproduction of gastric acid, resulting in recurrent peptic ulcers.
25% time linked to MEN1
overall survival rate of gastric cancer
15%
what 3 histological changes are seen in coeliac disease
villous atrophy (flat villi) crypt hyperplasia increases intraepithelial lymphocytes
give the diagnostic criteria of coeliac disease
endomysial antibodies - anti EMA
tissue transglutaminase antibodies - anti TTG
AND a biopsy
on gluten rich diet showing villous atrophy
off gluten rich diet showing normal villi
